J.A. Yoder is an educator and engineer who has a lifetime love of puzzles and patterns. Her educational philosophy is that hands-on creative work is both the most fun and the most effective way to learn. She developed and taught the original hands-on-math lessons for an after-school program that eventually inspired this book. Some of her happiest memories come from "eureka moments"—either from learning something that makes a dozen other things suddenly make sense, or the sense of accomplishment that comes from solving a clever puzzle. The only thing better is sharing this joy with others.